Of the many different zones in Minecraft Dungeons, there are even a few hidden ones. As you progress through the game, you will be given various missions to complete, some of these also lead to new areas. Players will find that some of these zones will send you hunting for unique dungeons. For example, the first mission, Creeper Woods, has a dungeon called Creepy Crypt. This dungeon is part of the story and is unlocked when you unlock the first access point in Creeper Worlds. From there you will also find other zones with similar setups. One mission, in the Soggy Swamp, has the player hunting down the Soggy Caves.
This zone and dungeon combo is actually a pretty good place for farming. Head here in the earlier parts of the game and get some good loot. You need to complete the previous dungeon run in Creepy Crypt first though, so go do that. That first dungeon is also good for loot too.
While exploring Soggy Swamp, the entrance for Soggy Caves in Minecraft Dungeons is found in the second section of the overall map. Head there for starters. Complete the first part of the mission here by heading inside and fighting and killing the Enderman. Head to the other side of the map and look for the entrance to the Soggy Caves. The Soggy Caves entrance is usually on the left side of the map.
There are two entrances here, one has a horse-like layout, avoid that one. The correct way into the Soggy Caves in Minecraft Dungeons is nearby to some ruins. Once you find this entrance, a smaller dungeon will greet you. Complete this mini-dungeon to unlock the map for this zone.
Finish out the rest of the tasks you might have in Soggy Swamp, Soggy Caves will be unlocked on your map. You can come back here and explore all you want now.